The invention concerns bobbins for sewing machines, and more specifically relates to a bobbin storage device to retain bobbins of various sizes, for convenient retrieval.
Bobbins for use on sewing machines, particularly domestic sewing machines, generally are of metal or plastic, shaped as a spool with two circular disks held in spaced relationship by a cylindrical hub at the center of the bobbin. The bobbin is mounted on the sewing machine via a central, axial through hole defined by the cylinder of the hub. When bobbins of various sizes are stored for occasional use on the sewing machine, they are sometimes stored using this center through hole, to stack the bobbins together on a rod, or in a box having individual molded half-cylindrical recesses to hold bobbins, but not in a way to retain the bobbins.
The invention now described retains the bobbins in a different and more convenient manner. Instead of using the center hole for retention of a series of bobbins, the device of the invention grips the bobbins by their peripheral edges, in a flexible manner allowing easy placement and retrieval of bobbins, as well as accommodation of a range of different bobbin sizes.
Most broadly, the invention comprises a flexible trough which in cross section defines a generally arcuate shape of somewhat greater than a half circle, thus being open at an outer side. The trough may be formed of urethane or other flexible, rubbery material which when deflected tends to return to its original shape. The internal diameter or width of the flexible trough is such as to be capable of gripping the smallest-diameter bobbin of a series of bobbins, when the bobbin is inserted into the trough device by pushing it between the side walls and fully into the trough, in an orientation in which the bobbin and the trough are essentially coaxial. The flexible, rubbery material permits retention of a wide range of bobbin diameters.
A preferred form of the bobbin retention device is in an annular shape. The ring-shaped trough forms an approximate partial toroid, so that the bobbins can be positioned in an annular arrangement.
It is thus a main object of the invention to store bobbins, particularly bobbins used on a domestic sewing machine, in a convenient and readily retrievable manner, accommodating a range of bobbin sizes in a simple device. These and other objects, advantages and features of the invention will be apparent from the following description of a preferred embodiment, considered along with the drawings.